final report grade 8
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Final Report, grade 8
Medical Instruments B: Quality Assurance in Design (Technische Universiteit Delft)
lOMo RPS
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INHOUD
Part 1 | General background and familiarization ......................................................................................... 3
A | Current surgical procedure ............................................................................................................. 3
B | Estimation annual sales ................................................................................................................... 3
C | Class of medical device ................................................................................................................... 4
D | ISO 14971 ........................................................................................................................................ 5
E | Usage ............................................................................................................................................... 6
Part 2 | Risk analysis ..................................................................................................................................... 8
A | Misuse ............................................................................................................................................. 8
b | Known and forseeable hazards ..................................................................................................... 11
C | Quantification of over-inflation .................................................................................................... 12
D | Hazards ......................................................................................................................................... 13
E | Inherent safety by design .............................................................................................................. 14
F | Conclusions on risks....................................................................................................................... 15
Part 3 | Manufacturing ............................................................................................................................... 17
A | ISO13485 manufacturing and quality control ............................................................................... 17
B | Material ......................................................................................................................................... 18
C | Manufacturing flowchart .............................................................................................................. 20
Part 4 | Technical documentation and CE-marking .................................................................................... 23
A | Formulation design criteria ........................................................................................................... 23
B | Have the design criteria been met? .............................................................................................. 23
C | Definitions in quality control ......................................................................................................... 24
D | CE marking route .......................................................................................................................... 25
E | Relations CE, MDD, ISO13485 and ISO14971 ................................................................................ 27
Part 5 | Evaluation of the medical device in the hospital ........................................................................... 28
A | Cleaning ......................................................................................................................................... 28
B | Literature on safety and performance .......................................................................................... 29
C | Clinical evaluation ......................................................................................................................... 30
D | Sample size.................................................................................................................................... 30
E | Medical ethical committee ............................................................................................................ 31
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F | Device recommendation ............................................................................................................... 31
Part 6 | Implementation ............................................................................................................................. 32
Appendices .................................................................................................................................................. 34
A | ISO 14971 ANNEX C ....................................................................................................................... 34
References .................................................................................................................................................. 35
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PART 1 | GENERAL BACKGROUND AND FAMILIARIZATION
A | CURRENT SURGICAL PROCEDURE
Describe the current surgical procedure as it is performed now, without the use of the chosen prototype that
you selected.
Minimal invasive surgery (also often called laparoscopic surgery) is a surgical technique which uses small openings
and long pencil-like instruments to do surgery. Some applications are bowel resection, organ removal, gastric
bypass.
To make the access to the internal body a trocar is used. The trocar is a medical device which will be inserted in the
in the abdomen by a triangle shaped point at one end. This needle is typically inserted inside a hollow tube, also
known as a cannula or sleeve. With the point the trocar will create an opening in the body to create an access port
for instruments during surgery.
Often, before inserting the trocar, a Veress needle is placed prior to the placement of the trocar. This needle will
provide the gas into the internal part of the body to prevent risks of injuring the underlying tissues. Carbon dioxide
gas is injected to inflate the abdomen to create a larger internal space to operate. If a laparoscope is inserted via
the first trocar, more trocars can be placed more easily under laparoscopic observation to reduce risk of injury.
When the trocars are placed the medical instruments such as graspers, scissors can be inserted through the new
cannula of the trocar. [1] The use of the minimal invasive surgery has a lot advantages, such as reduced
postoperative pain, improved cosmetic results and reduced hospital stays. [2] [3]
B | ESTIMATION ANNUAL SALES
Make a rough estimation of the potential annually sold numbers of the chosen medical device prototype in
Europe. Use estimates of the number of surgical procedures performed, number of surgeons or hospitals in
European countries, number of residents in Europe and an estimation of the expected market share.
An estimated 2,5 million of laparoscopic surgeries are performed in USA. Of all surgeries to the digestive system
almost 100% is done laparoscopic these days. These numbers are drawn from the interview of MD. Ronald A.
Rhodes [4]. Because of lack of other numbers we will use these numbers also for Europe in order to have a realistic
estimation based on real market needs.
In 2010 Europe counted on average 2,7 hospitals per 100.000 inhabitants [5]. With a population of nearly 500
million people, this makes a total of 13.500 hospitals. Let’s say 70% [own estimation] is active in minimally invasive
surgery, leaving out small private clinics, and hospitals in less wealthy countries. This makes a total of 9450
hospitals. However, not all hospitals will be using PortShield so we estimate that 20% (1890 hospitals) of these
9450 hospitals will use it from the beginning.
An estimated average of more or less 265 [2.500.000/9450] laparoscopic surgeries are done annually in each
hospital.
This product will not be used for all laparoscopic surgeries since not all of the surgeries will be in the abdominal
area, and in the first instance hospitals might be holding on to older devices used in these kinds of procedures. An
estimation is done of an average 133 annually supplied laparoscopic surgeries per hospital [50% of estimated
laparoscopic surgeries].
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With 1890 hospitals and 3 trocars per surgery as stated by MediShield, this gives an estimate of 754.110 annually
sold items.
The number of clinicians is not taken into account, because this device is used only once and thrown away after
the procedure. Therefore it does not matter how many surgeries are done per day and by how many physicians
precisely.
Unit market share: The units sold by a particular company as a percentage of total market sales, measured in the
same units. [6]
So for 2,5 million laparoscopic surgeries where 3 trocars are used for each surgery, we estimate a total market unit
sale of 7,5 million items.
Unit market share (%) = 100 * Unit sales (#) / Total Market Unit Sales (#) =>
Unit market share (%) = 100 * 754.110 / 7.500.000 = 10%
C | CLASS OF MEDICAL DEVICE
Identify the class in which the medical device prototype can be categorized.
All surgically invasive devices intended for transient use are in Class IIa as stated in [7] [8] (M5 paragraph 2.2 Rule
6).
Figure 1 flowchart class categorization [8]
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D | ISO 14971
Use the ISO 14971 standard and try and answer all questions stated in Appendix C. Skip the questions that do
not concern your chosen medical device prototype. Be critical in answering the questions, if you do not know
the answer or need additional information or calculations to support an answer please state this. It is a first
exploration of the current prototype is already suited to pass the CE-marking application. Based on the answerof question 1b, choose whether the device will be a disposable or a reusable product.
Table 1 Answers to ISO 14971, Appendix C
Question * Answer
1 This device is used to prevent gas leakage and shifting of the used trocar. The PortShield consists of
a balloon that can be rolled down the trocar tube before surgery. The trocar tip can then be
inserted in the patient using the surgeon’s own preferred technique. When the trocar has been
placed, the balloon is inflated, fixating the trocar in the port site. The variable wall thickness ensures
the anchor shape is maintained when an upward force is applied on the trocar . A solid wire inside
the balloon ensures the balloon can be fully deflated before removal indications of use (na vraag b)
The device is created to be used one procedure.
In case of breaking of the device in the body it can be possible that parts of the balloon have to beretrieved from within the body.
if the device refuses to work no special intervention is necessary.
2 no, the device is not intended to be implanted
3 the device will be in contact with the opening in the human body during the endoscopic procedure.
This can be considered as invasive contact, since part of the device is used inside the body.
4 the device is made of rubber and plastic. It will be in contact with materials from used trocars.
8 The medical device is transient and used only once. It is supplied sterile and no sterilization by the
user is needed
13 the device is intended to be used in combination with regular trocars of sizes 3-5 and 10-12 mm.
Problems that can occur are bad fixation of the rolled down balloon to the shaft of the trocar. Also
penetration of the balloon when fixating it to the trocar can occur.14 if not sufficiently inflated, the balloon may apply too much pressure on the incision or even burst.
15 rubber can dry when stored too long in a dry or hot environment. With very high temperatures
plastics may melt or burn.
20 it may be necessary to set an expiration date in terms of life expectancy of the balloon. The shelf life
of the balloon is significantly shorter than that of the body of the device. The body can be recycled.
22 forces applied are under control of the user. the balloon is inflated using a manual inflation device.
23 the expiration date of the balloon should be considered as an ageing factor for preventing the use
of the device.
24 Yes, device is intended for single use. The device has to be manually removed from the trocar. The
device will then probably be dirty and directly thrown away. The device should be used only right
after the package is removed.25 The device has been in contact with the inside of a human body and it is possible that it has been in
contact with dangerous microorganisms. Therefore it has to be properly disposed of. Materials used
are recyclable.
26 A small instruction should be given but the basic insertion technique is the one surgeons were
trained to use in minimally invasive surgeries.
27 Instructions for use are provided directly to the end user by the manufacturer. Since the use only
considers three main actions specifically for this device. The rest are actions the surgeon is already
familiar with, depending on the procedure done.
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29.3 The only connecting part to the device is the pump used to inflate the balloon. Lack of feedback
might burst the balloon inside the patient.
29.7 The device will be used only by trained surgeons.
31 not inflating the balloon
deflating the balloon/not closing it properly during the procedure
not rolling the balloon down before inserting the trocar
over inflating the balloonreusing it on another patient
* The actual questions can be found in appendix A
E | USAGE
Describe step by step how the medical device should be used. To start this process, first identify all people who
will have to handle the device at some point.
Table 2 Usage of the medical device
Step 1 Manufacturing The medical device has to be
manufactured in sterile
environment
Keep sterility
quality control
Step 2 transport to hospital the device has to be transported
in dry conditions away from heat,
light and exposure to the air
[https://www.balloonhq.com/faq
/care.html]
Keep sterility
safety measures, so package will not
be damaged
Step 3 storage in hospital the device has to be stored away
from heat, light and exposure to
the air
[https://www.balloonhq.com/faq/care.html]
Keep sterility
safety measures, so package will not
be damaged
Step 4 unpacking the device has to be removed
from the sterile packaging. By a
nurse or the surgeon.
keep sterility
follow instructions
Step 5 attach to trocar the device is now attached to the
trocar by either a nurse or the
surgeon
keep sterility
mind not tearing the balloon
Step 6 rolling down balloon the surgeon or nurse rolls theballoon over the shaft of the
trocar
to be completely rolled down so thatthere no complications are caused
during inflation
Step 7 Inserting trocar in
body
the surgeon inserts the trocar
into the body of the patient
make sure balloon does not roll back
over the shaft of the trocar
Step 8 Attach air tube air tube is connected to valve for
inflation of balloon by nurse or
surgeon.
follow instructions
make sure air tube is properly
attached
Step 9 Inflating balloon after The nurse or surgeon uses a make sure balloon does not burst due
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insertion. pump to inflate the balloon inside
the body
to over inflation
Step 10 Removing air tube* the tube is disconnected to avoid
it being in the way of mobility of
the instruments. (?)
make sure balloon is not deflated by
accident.
*Not clear if tube is removed before
or after procedure
Step 11 Performing plannedprocedure
-- --
Step 12 Deflating balloon using built in valve, or by
retracting air with a manual
device, the balloon is deflated. By
the surgeon (or nurse)
not clearly visible if balloon is indeed
deflated. creates risk when trying to
pull trocar out.
Step 13 Removing air tube* *not clear if tube is removed before or
after procedure
Step 14 Rolling up balloon by either nurse or surgeon otherwise it is not easy to remove
device from trocar
Step 15 Detaching device by nurse (or surgeon) Be sure not to damage tissue of the
patient while removing it
Step 16 Disposing device by nurse (or other O.R. personnel) be sure to dispose/destroy it so itwon’t be reused
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PART 2 | RISK ANALYSIS
As safety is a critical issue in medical products, the quality and control processes of a medical device depend
largely on a thorough risk analysis. Guidelines and obligations for this risk analysis are available in the ISO 14971
standard (see Blackboard). In this assignment, you will make a risk analysis of the medical device prototype (or
in case you already have improved the design, the new version of the prototype). Finally, you are requested tomake a redesign of the prototype that minimizes at least one risk factor
A | MISUSE
Read Appendix A.2.4, A.2.5, B and E of ISO 14971 standard. Use the same list as set up in Assignment 1e, but
now describe for each step/action the possible misuse of the device. Take into account the different levels of
misuse e.g. the intended use, intended users, process of use, and involved equipment.
Table 3 Possible misuse of the medical device
Step # Name Description Intended user R# Risk Level of misuse
1 Manufacturing The medical device
is manufactured by
external party
factory
worker
R1 > Materials not properly
checked on biocompatibility
and pureness
involved
equipment,
intended users
R2 > Tools and equipment can
show wear
involved
equipment
2 Assembly Balloon and holder
have to be
attached to eachother
factory
worker
R3 > insufficient sterilization process of use
R4 > insufficient attachment process of use
3 Packaging device has to be
packaged sterile
and vacuum
factory
worker
R5 > not packaged intended
R6 > not vacuumed involved
equipment
R7 > packaging machine not
sterile
involved
equipment
4 transport to
hospital
the device has to
be transported in
dry conditionsaway from heat,
light and exposure
to the air [1]
[https://www.ballo
onhq.com/faq/care
.html]
transport
personnel
R8 > Transport out of package intended
R9 >mishandled duringtransportation
intended
R10 > transport under bad
environmental properties
intended
5 storage in
hospital
the device has to
be stored away
hospital
personnel
R11 > Storage out of package intended
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from heat, light and
exposure to the air
[2]
[https://www.ballo
onhq.com/faq/care
.html]
R12 > Bad environmental
properties
intended
6 unpacking the device has to
be removed from
the sterile
packaging.
O.R.
personnel
R13 > dirty environment, losing
sterility
process of use
R14 > damaging device [e.g.
when opening package with
something like scissors]
process of use
R15 > balloon already rolled
down, cannot be properly
rolled up again for
attachment
process of use
7 attachment to
trocar
the device is now
attached to the
trocar by either anurse or the
surgeon
Nurse or
surgeon
R16 > improper attachment unintended
R17 > attachment to wrongdevice
intended use
R18 > piercing balloon with tip of
trocar
involved
equipment
8 rolling down
balloon
the surgeon or
nurse rolls the
balloon over the
shaft of the trocar
Nurse or
surgeon
R19 > not fully rolling down
balloon
unintended
R20 > not rolling down balloon
at all
intended
9 Inserting
trocar in body
the surgeon inserts
the trocar into the
body of the patient
Surgeon R21 > device is inserted first,
than trocar inserted through
device
intended use
R22 > balloon rolls up again process of use
10 Attach air tube air tube is
connected to valve
for inflation of
balloon by nurse or
surgeon.
Surgeon R23 > not properly attached unintended
11 Inflating
balloon after
insertion.
The nurse or
surgeon uses a
pump to inflate the
balloon inside the
body
Surgeon R24 > inflate with wrong device intended use
R25 > inflate too much intended use
R26 > inflate balloon by mouth intended use
R27 > inflate too little intended use
R28 > does not inflate
intentionally
intended use
R29 > forget to inflate Unintended use
12 Removing air
tube (?)
the tube is
disconnected to
avoid it being in the
way of mobility of
surgeon or
nurse
R30 > forget to remove, tube
gets in the way of procedure
unintended use
R31 > decides not to remove
tube
intended use
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the instruments. (?) R32 > valve of device fails,
balloon deflates
failure at
manufacturing /
equipment
13 Performing
planned
procedure
Device is passively
present during the
procedure
surgeon R33 > trocar not properly sterile involved
equipment
R34 > material causes reactionwith tissue
material hazard
R35 > Gas leakage process of use
14 Deflating
balloon
using built in valve
(?), or by retracting
air with a manual
device, the balloon
is deflated. By the
surgeon (or nurse?)
surgeon or
nurse
R36 > forget to deflate unintended
R37 > balloon sticks to internal
body tissue
material hazard
15 Removing air
tube (?)
the tube is
disconnected to
avoid it being in the
way of mobility of
the instruments. (?)
surgeon or
nurse
R38 > because it is not yet
removed balloon could not
be deflated
process of use
16 Removing
trocar from
body
the trocar is
removed from the
body after the
minimal invasive
surgery has come
to an end
surgeon R39 > balloon sticks to internal
body tissue
process of use
R40 > parts of device can be left
in the body
R41 > body tissue from device is
dispersed by hands of
handler
process of use
R47 > it is forgotten to deflatethe balloon
Process of use
18 Detaching
device
by nurse (or
surgeon?)
nurse R42 > Decide not to remove it in
order to reuse it after
sterilization
Intended use
Nurse or
Surgeon
R43 > Forget to remove, balloon
remains attached at the
trocar
Unintended use
19 Disposing
device
by nurse (or other
O.R. personnel)
Nurse R44 > Body Tissue is dispersed
outside 'trash can'
R45 > Forget to dispose and
balloon is reused
Unintended use,
be sure to
dispose/destroy it
so it won’t be
reused
20 Recycling R46 > Not recycled as two
different parts (balloon and
holder)
process of use
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B | KNOWN AND FORSEEABLE HAZARDS
Read Appendix D of ISO 14971 standard. Describe known and foreseeable hazards in normal and fault conditions
when operating the medical device prototype by summarizing the risks and their severity in a table. Be as
complete as possible. Take into account purpose, intended use, intended users, process of use, involved
equipment, material, manufacturing process etc.
Table 4 Distribution of risks
Severity* >>
P r o b a b i l
i t y *
> >
negligible minor serious critical catastrophic
frequent R35
probably R38R44, R41, R19, R27,
R31R47
occasional R46, R23 R9, R37, R32R2, R22, R25,
R30
R10, R36
remote R29 R43 R14, R16R3, R4, R12,
R20
R5, R6, R7, R8, R11, R13,
R33
improbable R24, R28 R42, R21, R15 R17, R18 R40, R34, R26 R45
* interpretation of probability and severity can be found in Table 5
Table 5 Interpretation severity and probability
Severity Probability
Catastrophic: Results in patient death Frequent ≥ 10−3
Critical: Results in permanent impairment or life-threatening injury 10−4
> Probable ≤ 10−3
Serious: Results in injury or impairment requiring professional
medical interventions10
−5 > Occasional ≤ 10
−4
Minor: Results in temporary injury or impairment not requiring
professional medical intervention10
−6 > Remote ≤ 10
−5
Negligible: Inconvenience or temporary discomfort 10−6
> Improbable
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C | QUANTIFICATION OF OVER-INFLATION
Some of these risks could be determined on a semi-quantitative probability level using calculations, simulations
and estimations. Indicate one risk that can be quantified in this more or less scientific manner. Describe in detail
how you would execute such quantification measurements to indicate the probability of that risks. The
quantification could for example be performed by describing an experiment to determine required data or bydescribing technical calculations.
Definition of ‘risk’ and ‘hazard’
The Irish Health and Safety Authority defines the term risk as follows: ‘‘risk is the likelihood that a person may be
harmed or suffers adverse health effects if exposed to a hazard’’ [9]. A hazard in this case is described as: “…a
potential source of harm or adverse health effect on a person or persons’’ [9]. In other words: the risk is the
possibility that a person is harmed by a hazard and can be quantified on a probability scale. Where the hazard is
the direct cause of an injury.
Risk of over-inflation of the balloon (unintended use)
Over-inflation of the balloon is seen as a risk since it can cause the balloon to break, maybe even into multiple
pieces. This can lead to loose fractions of the balloon remaining in the abdominal cavity which is seen as a hazard
since it can directly do harm to the patient. Therefore the probability of over-inflating the balloon must be
determined to be able to take the next steps in controlling this risk.
Experiment to determine the risk of over-inflation
This experiment should consist of two parts. One is a technical experiment, to see at which pressure the balloon
will break. Second is a clinical experiment to see to what extent it is possible that the surgeon indeed inserts this
amount of gas into the balloon. From the outcome of these two experiments it would be possible how high the risk
of over-inflation really is.
1st
part of the experiment: Technical
Materials
- significant amount of PortShield devices
- air pump, electrical- electrical barometer
- software to record measurements
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- multiple tubes
Test setup
The PortShield device will be clamped so the experimenter will have free hands to conduct the experiment. The
balloon will be connected to the air pump using tubes, with the barometer in between. (Fout! Verwijzingsbron
niet gevonden.)
Figure 2 Test setup
Method
The balloon of the PortShield will be inflated until it breaks. This will be done a significant amount of times until a
proper conclusion can be formed about the maximum applicable pressure to the device. This maximum applicable
pressure will now be called ‘breaking pressure’ (BP).
2nd part of the experiment: Clinical/usage
Materials
- PortShield device
- Dummy abdomen
- Surgeon
- Air pump used in O.R.- Barometer
- Computer with software
- Questionnaire
Test setup
The PortShield will be attached to the dummy abdomen and attached to the manual air pump that is a lso used in
the O.R. Between the air pump and air pump the barometer will be attached which will send data to the computer.
Method
First the surgeon will manually inflate the balloon until he/she thinks the balloon is sufficiently inflated for good
fixation and prevention of gas leakage. This will be examined using a small questionnaire. The surgeon will do this
with a significant amount of PortShield devices.
After this the surgeon will take these PortShield devices again and test whether it is even possible to reach the BP
manually.
Results
From these two test, three results are obtained:
- Breaking pressure of the balloon
- Can the surgeon reach this breaking pressure when inflating the balloon manually
- How much differs the necessary pressure of the balloon from the breaking pressure: how big is the
safety margin?
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Conclusions
With these results it can be concluded how big the risk of over-inflation really is. When comparing the actual
breaking pressure with the pressure needed for proper fixation and the actual pressure that can be applied
manually it can be determined whether the risk on over inflation really is significant.
D | HAZARDS
Select two hazards from Assignment 2b. Indicate for each risk what type of measure is required: inherent safety
by design; protective measures in the device; and information for safety. Additionally, give for each hazard a
possible solution based on the selected measure.
Hazard 1
R25: Over-inflation of the balloon
Measure required: Protective measures in the device
Protective measures in the device are interpreted as changes that are not immediately visible in the exterior of the
product as it is, but do contribute to the safety. In contrast to ‘safety by design’ which is interpreted as a redesignwith clear visible changes in the design (like addition of parts)
To minimize the risk of over-inflation, a ‘smart valve’ can be introduced to the device. Since the device already is
equipped with a valve this can be considered as a protective measure. The idea of the smart valve is releasing
pressure when pressure gets too high. This way the breaking pressure of the balloon will never be reached. It has
to be determined what the ideal ‘release pressure’ would be which has enough range to breaking pressure but also
to necessary pressure for fixation and anti-gas-leaking.
Hazard 2
R10: Transport under bad environmental properties
Measure required: Information for safety
Warnings regarding proper environmental properties could be addressed on the packaging of the device. These
can include fragility, environment temperature, light and humidity warnings (Figure 3). Also an expiration date
should be added to the packaging (although his moreover includes storage).
Also a specialized transportation company should be assessed on this
Figure 3 warning examples [own design]
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E | INHERENT SAFETY BY DESIGN
Select one hazard from Assignment 2b. This hazard should be reduced by ‘inherent
safety by design’. Gather the SolidWorks drawings (see Blackboard) of the medical
device and make a redesign that minimizes this risk. If you cannot resist the urge to
make a redesign that reduces more risks, this is of course highly supported.
R47: It is forgotten to deflate the balloon before removing it
Type of measure required: Inherent safety by design
The current stage of the PortShield does not yet hold a safety measure to make sure
deflation is not forgotten. Since alarms are one of the most hazardous elements of
medical devices [10] it would be best if the risk is reduced by redesigning the product
itself.
Figure 5 Sketch of redesign for deflation safety Figure 6 Render of redesign for deflation safety
There is a fine line between inherent safety by design, and protective measures in the device. Although this
addition does not change the final goal of the product, it is a large change in the looks and size of the product,
therefor we interpret this as inherent safety by design.
With this in mind it is thought of the add a ‘safety slide’ to the device. This part will assure that when the trocar is
pulled out of the abdominal wall the valve to the balloon is automatically opened completely to quickly deflate the
balloon. This way the surgeon will not be able to pull out the trocar when the balloon is still inflated, since this
could cause rupturing of the abdominal wall.
Figure 4 PortShield
(Source: MediShield)
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As seen in Image 4 the ‘safety slide’ is added to the top part of the PortShield. When the safety slide is pulled the
valve to deflate the balloon is broken so the balloon immediately deflate due to pressure induced by pulling it out
of the abdomen. The ‘safety slide’ covers the top part of the trocar in such a way that the surgeon has to hold it
when pulling out the trocar. Since the trocar gets wider at the top, as seen in Figure 4, the safety slide is funnel
shaped. It has a cutout where the valve of the trocar is positioned.
F | CONCLUSIONS ON RISKS
Based on all information that you gathered for this assignment give conclusions on the risks of the medical
device.
Argue if the medical device prototype is safe to use after your redesign
As we already know, PortShield was designed in order to prevent gas leakage from the trocar and enhance fixation
during minimal invasive surgeries. Another driver for the design of the PortShield is costs, since fully disposable
trocars are very expensive [11]. Yet the use of a balloon in the abdomen brings risks that would not be present
when using a normal ‘naked’ trocar. Creating a safety stop reduces one of the risks the balloon brings, namely:
pulling the trocar out before deflation. This risk could cause the hazard of rupturing t he abdominal wall. However
this is not the only risk the balloon brings. In Table 3 more risks regarding the balloon can be seen. These are all
minor risks, but it does mean that the product is not risk free yet.
Suppose that you succeeded to reduce all risks to an acceptable probability level, argue if these residual risks
weigh up to the benefits of the device
In case we were able to reduce risks as stated in our table in 2b to an acceptable probability level, we believe that
residual risks would not only weigh up to the benefits of the device, but they would be overcome by the benefits.
This can based on that e.g. all catastrophic risks would become improbable and also remaining leakage probability
would be reduced significantly. Many other risks would be deleted and so the remaining risks, considering their
small severity, would not be able to weigh up to the benefits of the device. The benefit of this device is to make
minimal invasive surgeries safer by preventing as much as possible gas leakage from the trocar and providing the
same time flexibility to the surgeon without damaging the tissue or abdominal wall.
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PART 3 | MANUFACTURING
In this assignment we continue by exploring several aspects of ISO 13485 norm with a focus on the
manufacturing process of your selected medical device prototype and the quality control of that process.
A | ISO13485 MANUFACTURING AND QUALITY CONTROL
Read Appendix I of the Medical Device Directive (93/42/EEC). As you can see, this list sums essential
requirements that a medical device should fulfill. For several risks you have to define and test your own safety
measure. For other risks, like electrical safety, technical ISO standards describe design rules to comply with and
standardized tests that have to be performed by test houses. Pick one of the essential requirements from
Appendix I that is applicable for your medical device. Indicate in which ISO standard you can find guidelines to
make sure the medical device will fulfill that requirement.
Requirement:
From Appendix I of the Medical Device Directive (93/42/EEC) an requirement that is applicable on the PortShield is
13.3, as seen below:
The label must bear the following particulars:
a) the name or trade name and address of the manufacturer for devices imported into the community, in view of
their distribution in the community, the label, or the outer packaging, or the instructions for use, shall contain in
addition the name and address of the authorized representative.
b) details strictly necessary for the user to identify the device and the contents of the packaging;
c) where appropriate the word “sterile”
d) where appropriate the batch code preceded by the word ‘lot’ or the serial number
e) where appropriate an indication of the date by which the device should be used, in safety, expressed as the
year and the month;
f) where appropriate, an indication that the device is for single use;
g) if the device is custom-made, the words “custom made device’.
h) if the device is intended for clinical investigations, the words “exclusively for clinical investigations’.
i) any special storage and/or handling conditions;.
j) any special operating instructions
k) any warnings and/or precautions to take;
l) year of manufacture of active devices other than those covered by e) this indication may be included in the
batch or serial number)
m) where applicable, the method of sterilization
We decided to choose requirement 13.3 because of b) c) e) f) i) & l) of the requirement cover decisions which are
pointed out in Assignment 1d and 1e, like reusability, sterility, date on packaging.
ISO standard:
The ISO standard with guidelines on how to fulfill the chosen requirement is the ISO 18113-4:2009 [12]
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B | MATERIAL
Use the results of Assignment 1, estimated annual sales, to determine the main construction material of the
medical device and answer the following questions. Note: At this stage, you are allowed to make modifications
to the design of the prototype to improve the manufacturability, but keep the focus on the material for this
assignment.
Since the PortShield is a disposable device, it is favorable to be as cheap as possible, but still of high quality. The
estimated annual sales were estimated on 7.5 million items, which is high and thus allows it to produce the
product by mass production. The material which should be used has to be non-toxic and should be safe to use
inside the human body. To choose a right material, the Cambridge Engineering Selector (CES) is used. One of the
most important factors in choosing the material is that the material should be biocompatible. This means that it is
not causing injury, toxic or immunologic reaction to living tissue [CES]. If all the biocompatible materials are
selected in CES they can be categorized in different orders.
The different biocompatible rubbers are shown in Figure 7, selected on their price. Here we can see that Ethylene
vinyl acetate is a cheap material. To see if this material has also good properties the yield strength and young’s
modulus are checked (Figure 8) with on the x-axis the yield strength, and on the y-axis the young’s modulus. Here
we can conclude that EVA has as good elastic properties as
Figure 7 rubbers, ordered in price
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Figure 8 rubbers selection based on yield strength and young's modulus
What are the allowable margins for variations in the material?
The balloon has only around a millimeter thickness.. The elasticity is dependent of the thickness of the balloon and
the elastic properties of the material. First the balloon will rolled down. We assume that the diameter of the not
inflated balloon is as big as the diameter of the trocar, which is 3-5 and 10-12 mm. when inflated it will be around
40 mm. this means that the material will be stretched.
In the length of the balloon doesn’t have to be that precise (5 mm difference), but the thickness of the material
does has to be precise since the thickness determines the shape of the balloon. So we can assume that the margin
for the thickness should be around 0.1 mm.
What documentation/certification is required of this material?
Ateva Medical Ethylene Vinyl Acetate (EVA) [13] resins are fully compliant with various international regulatory
requirements for medical applications, including U.S. Pharmacopeia certification, European Pharmacopeia
certification and others. Drug Master Files are available to be referenced by Celanese customers, and testing for
additional USP requirements is offered. Widely accepted in medical applications including implanted products, EVA
polymers have been approved for use in numerous pharmaceutical and medical devices around the world.
Certifications and approvals may include but are not limited to:
• High purity products
• USP Class VI
• ISO biocompatibility• Drug Master File (DMF) listed
• Oral toxicity
• FDA extraction test
• Food contact compliance (FDA and EU)
• Absence of heavy metals/PFOA/ halogenated substances
• REACH compliant
• Free from additives derived from animal origin
• GMO-free
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• Phthalate-free
• Change management
What companies can deliver this material?
Ateva Medical EVA polymers [14] offer medical device companies flexibility in product design. They are
biocompatible, stable and display excellent resistance to tissue growth. Moreover, they can be processed at low
temperatures using a variety of manufacturing methods. EVA is optically transparent, offers good adhesion and
flexibility, boasts excellent tear, puncture, impact and water resistance and is breathable and clinically accepted
around the world.
How would you monitor the consistency of the material once you have chosen a s upplier?
To be sure that the material is of the right consistency a chemical analysis should be performed. This can be done
by chemical reactions or by x-ray [15].
By mechanical testing the material properties can be checked, for example yield strength, viscosity to make sure
that it is the right material. By X-ray the material structure can also be checked. [16]
C | MANUFACTURING FLOWCHART
Read paragraph 7.5 of ISO 13485 standard and use previous answers to questions. Make a flowchart from the
raw material to the final medical device product in which all necessary production machines/steps are present.
Discuss which one of these machines is most likely to cause risks/hazards or fluctuations in the production.
Propose a measure of control to monitor this risk or fluctuation.
Manufacturing process
The body component and the valve case are produced by injection molding. After manufacturing the dif ferent
components the device have to be assembled, including the ring, balloon, valve and valve case.
Following manufacturing steps similar to those of balloons and condoms [17], the following steps for
manufacturing are present:
1. Ethylene-vinyl acetate (also known as EVA) is obtained. Eva is the copolymer of ethylene and vinyl
acetate. The weight percent vinyl acetate usually varies from 10 to 40%, with the remainder being
ethylene.
2.
The compound is then added to the dipping machine. The dipping machine is a long, hooded machine
approximately 100 feet (30.5 m) in length. Thick tempered glass rods move along a closed belt between
two circular gears. The belt drags the rods, which are called mandrels, through a series of dips into the
EVA compound. The mandrels rotate to spread the compound evenly. Several coats are required to build
the condom to its required thickness. Between each dip, the compound is hot air dried.
3. After the final dipping and drying, the balloons automatically roll off the mandrels. A machine shapes and
trims the ring of EVA at the base of each balloon.
4. Vulcanization of the rubber, forming crosslinks (bridges) between individual polymer chains. Vulcanized
material is less sticky and has superior mechanical properties. [18]
5. Removing balloon from form.
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6. The balloon have to be checked by performing tests for safety
7. The balloons are being vacuum packed
Figure 9 Flow chart of manufacturing process
Machine causing dominant trouble
The machine that can cause dominant trouble will be the one which produces the balloon. This can cause
dominant trouble because the balloon will be the most complex and functional part in the device. If the
temperature of the latex in the machine is too high, the layer of EVA covering the mold will be too thin. This can
cause troubles because it will tear much easier. Also sharp edged can cause damage to the balloon.
Propose measure and discuss why this is a good one
The balloons should be tested if they are strong enough (not tear) and don’t leak. The same procedure as condoms
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can be used. In this testing procedure the balloons will be inflated with air so it enlarges. In this case it should be
around a cylinder (like a trocar). If the balloon bursts before it reaches a certain volume (which is bigger than the
volume which is used during surgery), it will fail the test and will be rejected. Also a randomly test should be
performed to see if the assembly of the device is done.
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PART 4 | TECHNICAL DOCUMENTATION AND CE-MARKING
Not only the device itself, but also the development process, the manufacturing process, materials,
management and quality control have influence on the safety of a medical product. Most of you have probably
heard of the ISO 9000 standard for which a lot of companies are certified. This standard regulates how a
company should take care that a certain level of quality is reached and sustained of both their product andprocesses. As medical devices are used a high risk environment where literally lives are at stake, the regulatory
administration has set up a special ISO standard for medical devices that is related to ISO 9000: ISO 13485. In
this course, we will focus on chapter 7 of this ISO 13485 standard, which is most directly related to the
development and design process which is the focus of this course. To be able to sell your medical device in
Europe, your product requires a CE mark. Steps to achieve CE marking will be addressed as well as its relation to
the other standards and guidelines.
A | FORMULATION DESIGN CRITERIA
Read paragraph 7.3 of ISO 13485 standard (see Blackboard). Formulate all design criteria of the medical device
based on the available information on Blackboard and the demands presented in paragraph 7.3 in a well-
organized scheme or template.
Aspect Part Criterium*
Sterility Whole device Device should be delivered sterile
Sharp
Edges
Entire device parts should not contain sharp edges
Air-tight (sealing) balloon,
valve,
no air should be able to escape from/through these parts
Toxicity all parts shouldn’t trigger allergic reactions
Inflatable balloon a valve should exist to be able to inflate the balloon
Deflatable balloon should be able to trigger the balloon to deflate
Grip shaft/balloon balloon around shaft of trocar should provide enough grip in the opening in
the abdominal wall
Handling Valve should be clearly visible and easy to operate in case of emergency
Grip holder holder should fit tightly on shaft of trocar
Materials all Should be applicable when used in invasive circumstances
Disposable all parts should be disposed after use
* These are criteria for intended use
B | HAVE THE DESIGN CRITERIA BEEN MET?
Based on the inventory that you made in Assignment 3a, determine which of the design criteria already have
been met and have been properly evaluated on a technical level using the available documentation on
Blackboard. Suggest how the at most three leftover criteria should be evaluated. For the latter, translate the
criteria first into a quantitative measure and suggest briefly how a test could be executed.
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Aspect Tested
yes/no
Result
Additional testing/calculations required yes/no
Evaluation proposal
Sterility no After manufacturing, the device has to be sterilized and packaged. According to the
sterility assurance predicament: After an item is sterilized we are not able to verify itssterility. The only way to test if it is properly sterilized, is to test regularly (preferably
before every use) the efficacy of the sterilizer in two steps:
Physical Monitoring: It helps to detect malfunctions by regularly check the sterilizer’s
temprature, time and pressure
Biological Indicators: are paper filter strips inoculated with millions of spores and are
used by sterilizer’s manufacturers to measure the sterility process
Disposable no no
Toxicity yes,
material
check
Sensitization studies determine whether a material contains chemicals that may
cause problems after exposure. We recommend the Guinea pig maximization test by
Magnusson & Kligman where: the test animals with a technically enhanced immune
system are exposed intradermally to the test material, and if 15% of the used animals
have a negative reaction to the material then the test is considered positive.
air tight nowhere
to be
found
The bubble test is the easiest method for leak detection. A container is filled with
water and the inflated balloon is dipped under the water. From a leak there will be
some bubble emission. To measure the leak rate is not impossible but needs
collection of the bubbles, measure their volume and divide this volume by the
measuring time.
Another way is to use a gas detector.
C | DEFINITIONS IN QUALITY CONTROL
Some definitions. Describe the following terms in your own words and give at least two references where more
information can be found .
What is CE marking?
CE stands for Conformité Européenne. [19] This mark states that “the product is assessed before being placed on
the market and meets EU safety, health and environmental protection requirements.” [20] When this mark is
aquired it means that the product may be sold in the European Economic Area (EEA). Does not mean that the
product has to be produced within the EEA. This regulation creates two standards: one for businesses that all have
to relate to the same rules, and one for consumers who are sure that all products they buy in the EEA are of the
same quality and safety standard. A mistake often made is that CE marking means the product is stated safe by
authorities like the EU, but CE markings can be assigned by a notified body (NB or NoBo), which a third party that is
accredited by the authorities. You can recognize a true CE mark from being shaped out of two colliding circles.
Often accompanied by four numbers noting the notified body it was assessed by.
More information to be found at:
Rijksoverheid [21]
DEKRA [22]
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What is the Medical Devices Directive?
The Medical Device (MD) Directive is a set of documents set up around 1993 in the EU to harmonize legislations
regarding medical devices. This was a new approach in the 1990’s. For a manufacturer to place a medical device on
the market all requirements from this directive have to be met [23] after which a CE-mark can be obtained.
Besides the Medical Device Directive (93/42/EEC) there are also the Active Implantable Medical Device Directive
(90/385/EEC) and the In Vitro Diagnostic Device Directive (98/79/EC) [24]
More information to be found at:
European Commission [25]
Revision of the Medical Devices Directive, European Commission [26]
What is a notified body?
A notified body (NoBo or NB) is an independent organization that investigates whether a product meets certain
standards in order the manufacturer to label the product with the CE mark. A NoBo is appointed by the
government of a country and by that goverment notified to the EU. Often a NoBo has a certain area of expertise.
For example: DEKRA Certification B.V. can, among other things, certifies medical devices, where Lloyd’s Register
Nederland B.V. focusses on Dutch railways. [27]
More information to be found at:
Emergo Group [28]
What is conformity assessment?
Conformity assessment implies checking whether a product meets certain technical aspects and fulfills specific
requierments. Mostly conformity assessments are based on one international standard, often ISO. Which brings
different parties closer together by making them work with the same references. Also it creates clearer
competition between companies, because: if you can state whether you product is for example safe, you can have
competative benefits relative to other companies. Also it provides consumers with added confidence, and helps
regulators ensure health, safety and environmental conditions are met. Elements of Conformity assessment could
be testing, certification or inspection. [29]
More information to be found:
ISO [30]
UK Government [31]
D | CE MARKING ROUTE
Determine based on the classification of your medical device, which CE marking route should be followed.
Present a flow chart. Discuss at what stage in the route the medical device currently is and indicate it in the flow
chart.
The classification of the PortShield is in class IIa. The steps that should be followed based on this classification are:
1. The conformity Assessment Route needs to be chosen. This can be done by the flowchart shown below in Figure
10. There are two ways to do this, however we would choose the first way due to the simplicity in steps but also
the completeness of this choice in addition to the other:
- Follow the procedure of the EC declaration of conformity found in Annex II, the full quality assurance.
- or follow the procedure of the EC declaration of conformity set out in Annex VII coupled with either the
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procedure relating the EC declaration of conformity of verification of each product or batch of products
(Annex IV), the procedure of production quality assurance (Annex V) or the Product Quality Assurance
(Annex VI)
2. The Technical File has to be compiled
3. The Declaration of Conformity
4. Appoint an Authorised Representative. (Hold the Tech Files for inspection by the Competent Authority)5. Vigilance and Post Market Surveillance. (affix CE marking & market the products)
Figure 10 Flowchart CE marking [32]
Stage
The medical device is currently at the step where there are some minor risks, still we are not planning to make any
further design changes and have to start preparing the technical documents that are required to be compiled.
These documents are important to obtain the declaration of conformity. These technical documents should bevery detailed and should contain everything about design, development, manufacturing of the device and the
conformity of the device to the harmonized standards.
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E | RELATIONS CE, MDD, ISO13485 AND ISO14971
Indicate the relation between the CE marking, Medical Device Directive, ISO 14971 and ISO 13485. You can a
give description, but you can also create a flow chart or drawing with some additional comments.
Figure 11 Relation CE, MDD and ISO 13485 and ISO 14971
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PART 5 | EVALUATION OF THE MEDICAL DEVICE IN THE HOSPITAL
Once you have manufactured your medical device product using a quality controlled process and the zero-series
had received CE marking, you have to proof that your new medical device is truly safe and offers the intended
benefits. Guidelines to set up a proper clinical evaluation study design are described in ISO 14155. The protocol
of clinical evaluation study first needs to be approved by the Medical Ethical Committee of the hospital beforeyou can start. This trajectory should ensure that patients are not exposed to unsafe products and poorly
designed studies that do not provide the answers to your study goal.
A | CLEANING
Let us assume that your medical device product turned out to be a reusable product. This implies that the device
should be sterilized, but more importantly should allow thorough cleaning. Gather the SolidWorks drawings of
your redesigned device (see Assignment 2) and argue if the device in its current form can be cleaned properly. If
not, redesign one aspect of the medical device that overcomes one of the cleaning problems.
What if PortShield is a reusable device, can it be cleaned?The PortShield is intended for single use. Therefore now the only thing that is really important is sterile packaging,
to provide sterility when using the device. After the procedure the PortShield will be thrown away and thorough
cleaning after the procedure is not needed.
If the PortShield turned out to be a reusable product, the device should be cleaned and sterilized. With the current
device this will not be that easy, mostly because of two reasons:
1 – Some parts cannot stand high temperatures
2 – accessibility of small parts and groves
Since most common sterilization techniques use high temperatures [33] (from 120°C) is will not be able to sterilize
the balloon properly. Either proper materials should be used for the balloon so sterilization will be possible. Or the
PortShield should be designed in such a way that some parts are reusable and some are for one time use. The
balloon could be such a part.
Accessibility of parts applies to the inflation tube that connects the bottom of the balloon to the valve. Since this is
a relatively long and very narrow tube it is very hard to clean. A solution for this problem should be found as well,
or this also has to be a disposable part. This would be easiest if this tube is integrated within the balloon for easy
attachment and detachment. Accessibility also applies to different parts that do qualify for sterilization. Since the
PortShield consist of different parts and these parts are attached to each other, small slots at connection places
occur. This is also something that should be considered when the PortShield would be reusable. A possibility is to
make all parts detachable so they can be sterilized separately
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Drawing of redesign to improve cleaning and provide
argumentation why this is the case
Assuming that the body, safety slide and valve case (Figure 1)
are already detachable from each other. It is now necessary
that the non-reusable balloon can be properly attached to
the reusable body. The attachment should provide proper
sealing to prevent the balloon from deflating. Also the
inflation tube that runs inside the balloon must be properly
attachable again. Therefor the body has to be redesigned.
Figure X shows the current design of the body. This shows
that the entrance for the inflation tube interferes with theattachment grove of the balloon. This makes it impossible
to create airtightness. In the current prototype the balloon
is tightened extra using a rubber band. Yet in the final
product it would be beneficial to have as little parts as
possible, to decrease production and assembly costs.
Figure X shows a redesign of the body. With only twoactions the new balloon can be attached to the part:
1st
– the inflation tube is inserted in the attachment tube
2nd
– the balloon is inserted in the attachment grove
Now the balloon is automatically hold tight when the body
is slid over the trocar because of the inwardly projected
clamping arm.
B | LITERATURE ON SAFETY AND PERFORMANCE
Read Appendix X of the Medical Device Directive (93/42/EEC) and ISO 14155 (see Blackboard). Perform a
literature search to determine if ‘a critical evaluation of the relevant scientific literature’ is available and might
already indicate safety and performance that could convince the Medical Ethical Committee of the intended
benefits of the device’. If so, describe the results briefly and give references (max. 300 words).
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As Bhoyrul et. al. [34] mentioned the slipping of the trocar is the most annoying problem in minimally invasive
surgeries. According to Tsivian et. al. [35] port site metastases is influenced to some extent by surgeon and OR
team, therefore it could be prevented by fixating trocar to prevent dislodgment or prevent gas leakage along and
around the trocar. So they came up with a cheap disposable solution by which the trocar is fixed to the skin with
an 00 suture and tied around the insufflation nipple to prevent extraction of the trocar [34]. Also tape is wound
around the basis of the trocar to prevent pushing the trocar inside. This method has almost eliminated trocarfixation and extraction but also prevented gas leakage because the trocar fits closely to the fascia. This fixation
method uses simple, cheap and readily available materials.
C | CLINICAL EVALUATION
Use the results of Assignment 1d, 1e and 3b to formulate a study goal for clinical evaluation in the operating
room. Include at least one objective measure and if applicable formulate a hypothesis.
Goal:
There are two clinical aspects that have to be tested. First there is the impact the device has on the current
procedure of laparoscopic surgery. This impact can be interpreted in different ways, but most logically would be
time of the procedure. The difference in time the procedure takes with and without usage of the PortShield could
indicate whether using this device interferes with usability or maneuverability of the other instruments or if it
might cause the risk of over exposing the patient to anesthesia. Second, the clinical goal of the PortShield in the
O.R. should be tested: prevention of gas leakage. We would want the gas leakage to be significantly less than
without the use of this device.
Hypotheses:
1) Abdominal laparoscopic surgery takes longer when using the PortShield than without making use of the
PortShield
2) Gas leakage during abdominal laparoscopic surgery is reduced when using the PortShield in the procedure,
relative to abdominal laparoscopic surgery without use of the PortShield.
D | SAMPLE SIZE
Based on all available information perform a sample size calculation of the number of patients required to
achieve the research goal. Describe the data that were used to perform the calculation.
Using the power calculation program G*Power version 3.1.9.2 the ideal sample size for these studies is calculated.
Since it is clinical research performed in vivo on human subjects it is very important that a secure estimation for
sample size is made.
The first hypothesis, abdominal laparoscopic surgery takes longer when using the PortShield than without making
use of the PortShield, can be tested with a two-tailed t-test, measuring the difference from a constant value. Sincethere is a lot of literature available on the duration of laparoscopic surgery. This way there is no need for two
sample groups which will reduce the amount of subjects needed. With a desired effect size of 0.5, significance level
of 0.05, power of 80%, G*Power estimates the needed sample size at 34 subjects.
The second hypothesis, gas leakage during abdominal laparoscopic surgery is reduced when using the PortShield in
the procedure, relative to abdominal laparoscopic surgery without use of the PortShield, can be tested using a two
tailed t-test measuring the difference between two independent means. Lack of prior research in the amount of
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gas leakage in this device creates the need for multiple samples. With an effect size of 0.5, significance level of
0.05, power of 80% and equal group size, G*Power estimates a sample size of 64 subjects per group.
E | MEDICAL ETHICAL COMMITTEE
Medical Ethical Committee issues regarding patient research (wet WMO is Law on medical research). Describethe following aspects.
Patient inclusion criteria:
- People who need endoscopic procedure of the abdomen.
- Should be between 18 - 75 years old
- The patient must be able and willing to provide informed consent
Patient exclusion criteria:
- Patients in bad overall medical condition
- Patients without the ability to provide consent, like children or mentally disabled people.
- Patients with allergies for materials used in the PortShield
Indicate how the privacy of the patients will be guaranteed
To guarantee the privacy of the patients numbers can be used to identify subjects instead of their names. A subject
identification code list can be used to link the data to the subject. This code should not be based on personal
patient details such as initials and birth-date. (Template research protocol, WMO) Also privacy can be protected by
making sure that the data of the patients is treated confidentially and is only accessible for a limited amount of
people.
Discuss advantages and disadvantages for the participating patients in the study.
Advantages:
- The procedure may be performed better because of the reduction of gas leakage
- Patient contributes to medical research which could improve overall health care- Better monitoring during procedure because of usage of new device
Disadvantages:
- Possibility of device failure increases risk of the procedure
- Extra post-procedure monitoring to keep track of possible post-operative problems
- Risk of allergic reaction to materials used in PortShield
F | DEVICE RECOMMENDATION
Use the current knowledge to argue if you would recommend to bring this the device on the market?
We believe that PortShield is a win-win product. We would highly recommend to bring PortShield on the market
based on its purpose of use and its revolutionary design which will eliminate trocar fixation, gas leakage and make
minimally invasive surgeries more safe and easy while using a way more simple procedure of use, than other
known devices until now. However, we have seen that there is for sure still ground for optimization in design,
performance or material which will all make it more cost efficient which is probably the most important factor to
success and sustain on the market.
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PART 6 | IMPLEMENTATION
You have now identified multiple medical, technical, economic and safety criteria to which the new medical
device product has to adhere to. However, in practice we see that even if you fulfil these criteria 70%-90% of
inventions still fail to be actually utilized by healthcare organizations. In case healthcare organizations do use it,
widespread adoption can take as long as 15 years. This is called the ”Implementation Gap”. Implementation isthe pathway towards having the invention actually utilized in daily care practice; to become the new standard.
To achieve this, we need to determine the invention’s “Implementation Strength” during the design process and
pro-actively shape the invention to maximize this strength. The Implementation Analyzer is a software tool that
supports this complex task. In this assignment you will be taught the me thodology behind the implementation
analysis and how to use the tool on your own case. You will receive an individual username and password to use
the tool at the start of the course.
Provide the results of the implementation analysis
Figure 12 Average appreciation of innovation
Figure 14 Average investment in the change
Figures 12, 13 and 14 show the results of the HIP analysis. The stakeholders mentioned in this analysis are thesurgeon, nurse in hospital, patient in hospital (three core users), surgery assistant (indirectly operationally
involved) and the healthcare insurer (internal and external conditional agents). From left to right the dots in Figure
12 represent the following: surgery assistant, surgeon, healthcare insurer, patient and finally nurse in the bottom
right. This distribution means that the surgery assistant has the largest investment burden, and the patient has the
lowest. Which is logical when you realize that the patient actually is a passive user of this product. It does not
directly contribute to his/her healing or health, while the surgeon or surgery assistant gets extra handlings during
the surgery. The average investment in the change comes down to 2.75 (Figure 14) which is on the positive side of
Figure 13 Embracing level
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the scale. At first glance it is visible that distribution of the stakeholders at appreciation level is not right. This
means somewhere in the HIPP tool information was processed wrongly, since it is not logical that all users have
exactly the same appreciation for the device (which in this case even is negative, -1, Figure 12). That can also be
seen due to the ‘nurse in hospital’-dot in the bottom right corner of Figure 12 Embracing level.
The overall negative appreciation is probably caused by the fact that the information that is used to perform theHIP-tool analysis implies that the device is more expensive than the ‘regular’ procedure. This can causes the
appreciation of the healthcare insurer, and the direct users to drop. But in spite of the device being more
expensive than ‘naked’ laparoscopy (without balloon), it is a lot cheaper than usage of entirely disposable trocars
[3] that are designed to be used with an addition such as this balloon. Therefor this data can be interpreted
differently depending on the perspective of the users: do they come from ‘naked’ laparoscopy, or from expensive
‘disposable’ laparoscopy.
Discuss next steps that need to be taken to facilitate the implementation
Relative to other devices, like the trocar, used during laparoscopic procedures, it is easy for the surgeon and nurses
to use this device since it needs very little training or extra knowledge to use. But the PortShield does bring extra
steps before and after to unpack, attach, detach and dispose the device. These extra handlings bring the most
inconvenience for the surgeon and nurse. Therefore a redesign for reduction of total user steps could be beneficial
for the sales of this product.
Also the insures have to be convinced that this device will have a positive effect on mostly the financial side of this
procedure. It is feasible to introduce the product, but a good estimation of cost efficiency has to be made. This can
be done by making a good business model.
For the health care suppliers the benefits of the device should be clear. So first good tests of the benefits (less gas
leakage, less slipping of the trocar) should be performed to convince them. Here the price relative to totally
disposable trocars is also a very beneficial aspect of the device in the market.
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APPENDICES
A | ISO 14971 ANNEX C
1 What is the intended use and how is the medical device to be used?
2
Is the medical device intended to be implanted?
3 Is the medical device intended to be in contact with the patient or other persons?